Automatic railroad-signal



(No Model.) 2 Sheets-Sheet 1.

.A. J. GRIFFIN. AUTOMATIC RAILROAD SIGNAL.

No. 443,440. Patented Dec. 23,1890;

12E444 ammo I 844mm THE NORHAS runs no, Puma-mum, WESHINGNN, n, a.

U ITED STATES PATENT OFFICE.

ALONZO JACKSON GRIFFIN, OF IVILKES-BARRE, PENNSYLVANIA.

AUTOMATIC RAI LROAD-SIG NAL.

. SPECIFICATION forming part of Letters Patent No. 443,440, dated December 23, 1890.

Application filed anua y 9, 1890. Serial No. 336,373. (No model.)

To aZZ whom it may concern.-

Be it known that I, ALoNzo JACKSON GRIF- FIN, a citizen of the United States, residing at \Vilkes-Barr,-in the county of 'Luzerne and State of Pennsylvania, have invented a new and useful Automatic Railway- Signal, of which the following is a specification.

This invention relates to automatic railwaysignals; and it has for its object to construct a device of this class which shall be operated automatically by passing trains to actuate a danger-signal, which after the passage of the train shall be reversed and exhibit another signal to indicate that the train has just passed, after which the signal shall be automatically restored to its normal position.

The invention consists in the improved construction, arrangement, and combination of parts, which will be hereinafter fully described, and particularly pointed out in the claims.

In the drawings, Figure 1 is a sectional elevation of the signal-operating mechanism, showing also the signal in its normal or initial position. Fig. 2 is an elevation of the signal, showing the position of the same immediately after being operated by a train, but prior to the piston 22 of cylinder 16, with its attachments, being forced in an upward direction. Fig. 3 is an elevation showing the position of the signal immediately after the passage of a train, and with dotted lines indicating the table or platform 21 restored to normal position and the weight 31 partly restored, the signal having been rotated by said weight one-third of a revolution. Fig. 4 is a top view illustrating the construction of the signal and a portion of the operating mechanism.

' Like numerals of reference indicate like parts in all the figures.

One of the track-rails 1, at a suitable distance from the tower 2, supporting my improvedsignalin g apparatus,rests in a suitably constructed chair 3, to which is pivoted a lever 4, having an upwardly-extending arm 5, which extends slightly above the head of the rail, so as to be engaged by the Wheels of passing cars. The outer end of the lever 4 is connected pivotally with the upper end of the piston-rod 6 of an air-pump 7 of ordinary construction. Said piston-rod carries the piston S, which is provided with the downwardlyopening valve 9. The piston and piston-rod are forced automatically in an upward direction by the action of the suitably-arranged spring 10. The bottom of the cylinder of the air-pump 7 has a downwardly-opening valve 11, connecting with a pipe 12, the opposite end of which communicates with a cylinder 13. A check-valve 14 is suitably located in the pipe 12. The upper end of the cylinder 13 is connected by a valved pipe 15 with the lower end of a cylinder 16, and the lower end of said cylinder 16 is connected by a valved pipe 17 with the bottom of the cylinder 13. The latter is provided near its lower end with a vent or gage valve 18.

19 designates a piston arranged to move vertically in the cylinder 13, and having an upwardly-extending piston-rod 20, the upper end of which carries a table or platform 21. A similar piston'22, having an upwardly-extending piston-rod 23, works in the cylinder 16, and the upper end of the piston-rod 23 carries a table or platform 2%.

The air-cylinders 13 and 16, with their attachments, are located directly below the signaling mechanism in the tower 2, and it is obvious that this may be located at any desired distance from the air-pump, with which it is connected by the pneumatic tube 12. The signaling mechanism comprises a hub 25, mounted upon a transverse shaft 26, and having radially-extending vanes 27, 28, and 29, which are painted of different conspicuous colors, usually white, red, and green. The outer edges of the wings or vanes are eccentric with relation to the axis of the shaft 26, for the purpose of engaging the latch mechanism, which will be presently more fully described.

Suitably wound upon the shaft 26 or passing over a pulley or sprocket-wheel upon the latter is a rope or chain 30, to one end of which is attached aweight 31, which normally rests upon the table or platform 21. The other end'of the rope 30 carries a weight 32, which is lighter than the weight 31.

33 designates a suitably-arranged pulley over which passes a rope or chain 34, one end of which carries a weight 35, which normally rests upon the table or platform 21. The other end of the rope 34. carries a weight 36, which is lighter than the weight Another pulley 37 is arranged adjacent to the pulley 38, and over it passes a rope 38, one end of which has a weight 39, which normally rests upon the table or platform 24-, while its other end carries a lighter weight it).

Suitably secured upon a post orbracket 11 within the tower, adjacent to the signal-wheel, is a latch-plate 42, having slots 43 to enable it to slide upon the studs 44, by means of which it is secured to the said bracket. A suitably-arranged spring 45 serves to force the said latch-plate automatically in the direction of the signal-wheel. Suitably hinged to the edge of the latch-plate 42 are the two upwardly-opening wings or latches it; and 47, which are adapted to engage the edges of the wings or vanes 28 and 27, which are bent; in opposite directions, as will be seen at A suitable casing, as shown at 19, serves to protect the signaling mechanism inclosed in the tower.

The upper end of the cylinder 16 has a lat-- cral branch or opening 50, to which a signaling-whistle 51 maybe attached.

The operation of the invention is as follows: lVhen a train passes the point of the track at which the air-pump is located, the wheels of the cars coming in contact with the upwardly-extending arm 5 of the lever i will impart a reciprocating motion to the piston of the air-pump, thereby compressing the air in the cylinder 13, to which the air is conveyed from the air-p um p through the tube 12. The piston 19 will thus be forced upwardly in the cylinder 13, thus elevating the weight 31, which rests upon the table 21. The weight 32 at the opposite end of the rope or chain 30 will at the same time descend, thus rotating the shaft 26, carrying the signal-wheel, in the d irection indicated by the arrow for two-thirds of a revolution,or until the wing 29,which represents the danger-signal, is exposed in an upward direction, as will be seen in Fig. 2 of the drawings. When the wheel revolves in this direction, the eccentric edges of the wings on coming in contact with the latch will force the latter back against the tension of the spring 45, thus enabling the said latch to be easily passed. When the wing 29 is in a raised position, the adjacent wing 28 will engage the latch i6, and the wheel will thus be held from rotating in a reverse direction. When the piston 19 reaches the upper limitof its movement, the air will be forced through the pipe 15 to the cylinder 10, in which the piston 22 will now be forced in an upward direction, carrying upwardly the weight 39. The weights 36 and -l0 are connected with the hinged latches i6 and -17, respectively, by means of cords 55, which are normally slack. It will be seen that when the tables 21 and 2t, carrying the weights 35 and 139, are elevated the weights 30 and 40 will be lowered, thus straining the cords and serving to hold the latches i6 and -17 closed. The air displaced from the upper end of the cylinder 16 by the upward movement of the piston 22 in the latter serves to operate the signal-whistle .51, and said whistle will continue to be sounded by any surplus air which maybe forced into the cylinder 16 from the air-pump. It should here be stated that the weight 30, supported upon the table 24., should be less heavy than the weight of the table 21 at the upper end of the piston-rod 20, working in the cylinder 1 with the addition of the weight 35. \Yhen the t ain has passed the point of the track at which the air-pump is located and the said air-pump ceases to be operated, the weight 35 at the upper end of the pistonrod 20 will force the piston 15) downwardly in the cylinder 123, the air escaping from said cylinder through the vent 18. As the weight descends it. elevates the weight 36, thereby slackening the cord 55, which connects the said weight with the latch :tthwith which the wing 28 is at the time in engagement. The signal-wheel is thus permitted to rotate a onethird revolution in a reverse direction or until the wing 27 comes in contact with the hinged latch 47, which is held closed by the action of the weight 40, attached to the cord 38, the opposite end of which carries the weight 39. The table 24-,carryingthe weight 39, now begins to descend, the air from the cylinder escaping through the valved pipelT and vent 18, thereby eventually causing the said weight 39 to over-balance the weight it), elevating the latter and slackening the cord 55, which connects said weight with the latchplate 47, engaging the wing 27. The said latch-plate will thus yield to the pressure of the wing 27 and the signal-wheel. will be permitted to make an additional one-third revolution, which restores it to its normal position.

The signaling mechanism herein described may be connected elcctricallyor by means of suitablyarranged pneumatic tubes with suitable signaling mechanism located in a distant tower when desired.

The advantages of this invention will be readily appreciated. The construction is simple and comparatively inexpensive and is of such a nature as to cause the signaling mechanism to be operated unfailingly and automatically by passing trains.

Having thus described my invention, I claim- 1. The combination of an air-compressor, a cylinder connected with said air-compressor by a pipe having a check-valve, a piston movable vertically in said cylinder and having a table or platform at the upper end of its piston-rod, a signal-wheel mounted upon a rotating shaft above said platform, and a rope or chain passing over said shaft and providedat its ends with weights, one of which is normally supported upon said table or platform, substantially as set forth.

2. The combination of the aincomprcssor, the cylinder connected with the same and having a vertically movable piston carrying the table or platform at. its upper end, the signal-wheel mounted upon the shaft above IIO 443,440 a I a said platform, a rope or chain passing over said shaft and provided at its ends with unequal weights, one of which normally rests upon the table or platform, and latch mechanism to retain the said wheel in position,

spring-actuated latch-plate having the up-,

wardly-opening wings or plates and suitable operating mechanism, substantially as herein set forth.

5. The combination of the signaling-wheel having wings or vanes with eccentric outer edges, the laterally-sliding latch-plate having upward ly-opening wings, the weights suspended from said Wings, the counter weights adapted to hold the said weights suspended from the latch-plates normally raised orinactive, the mechanism for rotating the signalwheel, and suitable pneumatic operating mechanism, all constructed and arranged substantially as and for the purpose herein set forth.

6. The combination of the air-compressor,

the cylinders 13 and 16, the Valve-pipe 12,

connecting the air-compressor with the cylinder 13, the valved pipe 15,, connecting the up per end of cylinder 13 with the lower end of cylinder 16, the valved pipe 17, connecting the bottom of cylinder 16 with the bottom of cylinder 13, the vent at the lower end of the latter, the branch pipe extending from the upper end of cylinder 16 and having a signal- Whistle, the Vertically-movable pistons carrying tables or platforms at the upper ends of their respective piston-rod s, the rotating shaft carrying the signal-wheel having the wings or vanes provided with eccentric outer edges and outturned corners, the laterally-sliding spring-actuated latch having upwardly-opening wings, the Weights suspended from the latter, the counter-Weights normally supported upon the tables or platforms and connected cords passing over suitably-arranged pulleys, with the weights suspended from the latchplates, and the operating rope or chain passing over the shaft of the signal-wheel and carrying at its ends unequal weights, the

heavier one of which is normally supported upon the table or platform at the upper end of the piston-rod moving in the cylinder 13, substantially as and for the purpose herein set forth.

In testimony that I claim the foregoing as my own I have hcreto affixed mysignature in presence of two witnesses.

ALONZO JACKSON GRIFFIN. Witnesses:

R. P. ROBINSON, CHRIST. ANDERSON. 

